Water, Water Everywhere

Wednesday, April 18, 2012

Adjusting for better drainage starts with a look around the property. Where does the rain go, or stay, during a deluge? What happens after? If the lawn squishes when you walk across it for days, if puddles remain and mulch floats, you know there’s trouble. As important as it is to ameliorate these conditions, it is also essential to prevent further over watering. If you have an inground irrigation system, check that the rain monitor sensor is working to shut it off during rainy periods. When it’s necessary to use the system again, be sure pop-ups can emerge and that drip hoses are not clogged with mud.
When we were kids, spring rain filled the grassy ditches in front of our house and rose behind the levee across the street, sometimes to dangerous levels. We learned about sandbags at a young age, but luckily, the ditch system in the neighborhood did most of the work. Nowadays, ditches are less common in many areas than French drains and swales, and you should consider both if water does not move off of your property voluntarily. French drains are underground pathways lined with gravel and perforated pipe that channel excess water out to the street or elsewhere. Swales are above ground low places in the lawn usually. They are sited to catch water in wide open channels and direct it where you want it.
The signs of compaction in lawns and garden beds are especially obvious in rainy weather. Water stands in traffic patterns on the lawn and puddles in the mulch just stay there. You will want to bore holes in the mud where people walk so the grass can grow there again, or bow to the inevitable and create a real path there. Beds that do not drain may require major renovation to achieve better soil drainage, but it may be a simpler matter. Rake out the mulch, lower its level, and slope it to send excess rainfall away from plants. If you have a border plant like liriope, use a hoe to cut a small channel right behind the edging or between some of the plants. It will never be noticed, but can make a big difference in wet weather.
When plants repeated die in a bed that stays too wet and cannot be renovated, it’s time to plant a bog and channel other water into that area. Plenty of popular plants, from canna lilies to LA iris, are perfect for such spaces and add a wildly natural element to any landscape. The list of suitable plants also includes swamp spider lilies and papyrus, two plants that deserve much more attention than they get.
Container gardens can get water logged, too. Potting mixes that will not dry out after a day or so may need to be amended with ground bark to improve their drainage or moved when heavy rain threatens. Do not allow water to remain in the saucers that protect your porch or deck from staining when pots rest directly on their wood. Turn the saucer over and place the pot on top of it so water isn’t caught there. Or remove the saucer entirely and replace it with clay pot ‘feet’, the elegant notched devices that sit under the pot’s lower edge to elevate it. Water will shed, wood stays clean, and air circulation around the pot is greatly improved.
If I had gutters, I’d set up a rain barrel or other capture system to conserve rainfall for drier days to come. With the extreme weather we continue to face, you might need a barrel or two for the tomatoes come June.